The stability of a building depends on loadbearing structural steel. Steel loses its loadbearing capacity when its temperature rises above 550ºC, causing collapse of the building. If the steel is sufficiently insulated, however, the time to structural failure can be delayed sufficiently for occupants to escape. This is the principle of intumescent coatings. ln a fire, when the temperature reaches a critical level, an intumescent coating will undergo a chemical reaction that causes the coating to expand or “intumesce”. This reaction product forms an insulating layer that slows the rate at which the core temperature of the coated rises, and prolongs its structural integrity.
Primed steel in building structural frames
ln a fire, a chemical reaction takes place causing the Promat® Cafco® SPRAYFILM WB3 to expand. This forms an insulating layer that slows the rate the coated steel is heated and prolongs structural failure of this steel.